#include <stdio.h>

int main()
{   char arr1[] = "hello world!";
    char arr2[] = "############";
    int size = sizeof(arr1) / sizeof(arr1[0]);
    int left = 0;
    int right = size - 2;
    while(left <= right)
    {   printf("%s\n",arr2);
        arr2[left] = arr1[left];
        arr2[right] = arr1[right];
        left++;
        right--;
    }
    printf("%s\n",arr2);
    return 0;
}
